The gang managed the victims from a make-shift call centre at a residential address in Parkview Gardens, Brent Cross.

Krisztian Abel, of Green Lane, Ilford, pleaded guilty in August last year to conspiracy to traffic persons into the UK and within the UK for sexual exploitation, conspiracy to control prostitution for gain. He is now waiting to be sentenced.

Police believe the group of six - which Abel was a part of – was responsible for trafficking more than 120 women into the UK.

Croydon Crown Court heard how flights were booked for the women who were flown into London Stansted Airport, where they were picked up and taken to brothels across London – including Waltham Forest.

Abel’s sister Szilvia Abel was extradited to the UK from Hungary on the same charges as her brother, including threatening to harm or tell their families they were prostitutes.

The gang would retain their passports in order to exert further control over them.

Abel once forced a victim in her 20s to carry out sex acts with clients which left her with serious injuries, as punishment after she discovered the address of the brothel where she was being held.

The gang managed the victims from a make-shift call centre at an address in Parkview Gardens, Brent Cross.

They used more than 40 mobile phones to organise bookings on a commercial scale. They charged clients between £30 and £100 per hour.

Det Sgt Alan Clark, of the Trafficking and Kidnap Unit, said: “Many of the victims have been deeply traumatised by what this gang did to them, and displayed signs of severe distress when they told us what had happened to them.

He also added: “They came to the UK for regular employment, to earn money to make a better life for themselves and their families.

“Instead, they found themselves trapped and at the mercy of this abusive group. I would like to pay tribute to the bravery of these women during what has been a very lengthy case.”

Victims of trafficking are urged to call the Human Trafficking freephone 24-hour helpline, which is open seven days a week and operated by specially trained officers waiting to take their call. The number is 0800 783 2589.